Bug 672175 part.1 Implement MouseScrollHandler for Windows r=jimm

widget/windows/WinMouseScrollHandler.h

@@ -0,0 +1,44 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef mozilla_widget_WinMouseScrollHandler_h__
+#define mozilla_widget_WinMouseScrollHandler_h__
+
+#include "nscore.h"
+#include "nsDebug.h"
+#include "mozilla/Assertions.h"
+#include <windows.h>
+
+class nsWindow;
+
+namespace mozilla {
+namespace widget {
+
+class MouseScrollHandler {
+public:
+  static MouseScrollHandler* GetInstance();
+
+  static void Initialize();
+  static void Shutdown();
+
+  static bool ProcessMessage(nsWindow* aWindow,
+                             UINT msg,
+                             WPARAM wParam,
+                             LPARAM lParam,
+                             LRESULT *aRetValue,
+                             bool &aEatMessage);
+
+private:
+  MouseScrollHandler();
+  ~MouseScrollHandler();
+
+  static MouseScrollHandler* sInstance;
+};
+
+} // namespace widget
+} // namespace mozilla
+
+#endif // mozilla_widget_WinMouseScrollHandler_h__